Rapid custom intra-articular ligament reconstruction guide

Abstract

The present invention is a method of creating custom surgical guides based on the patient's unique anatomy that can be quickly and accurately applied intra-operatively without navigation are disclosed. The device is created using preoperative MRI images and uniquely conforms to the bone in the region of the desired tunnel. The images are filtered and used to generate computerized three dimensional models of surgical guides that conform to the patient's anatomy. The surgical guides can be introduced through a portal and applied to the bone denuded of soft tissue.

What is claimed is: 
     
       1. A method of creating a surgical guide, comprising the steps of:
 imaging a patient's joint; 
 collecting a set of images of the patient's joint; 
 generating a first mask on each image in the set of images; 
 processing the first mask to remove artifacts; 
 generating a second mask on each image in the set of images; 
 processing the second mask to remove artifacts; 
 merging the first and second masks creating a merged mask; 
 generating a third mask by filling in any holes in the merged mask; 
 creating a three dimensional image of the third mask; 
 generating a reverse image of the three dimensional image of the third mask; 
 creating a template from the reverse image; and 
 manufacturing a surgical guide from the template. 
 
     
     
       2. The method of  claim 1 , wherein the surgical guide further includes:
 a body having a first end, a second end, a contacting surface, and a top surface; 
 a tooling guide disposed near the second end and at a ligament attachment point; 
 the first end adapted to fit in an interstitial space between a set of bones in the joint; and 
 the contacting surface inversely contoured to a shape of the patient's joint anatomy. 
 
     
     
       3. The method of  claim 2 , wherein the tooling guide is selected from a group consisting of a guide cut out, drill guide, and groove tracks. 
     
     
       4. The method of  claim 2 , wherein the tooling guide is adapted to accept a tool selected from a group consisting of an awl, drill, osteotome, dental hatchet, burr, and coring reamer. 
     
     
       5. The method of  claim 1 , further including a step of cropping the merged mask to highlight an attachment point of a ligament. 
     
     
       6. The method of  claim 1 , wherein the images being collected have an image slice thickness of 0.499998 mm and patient image orientation of RAX. 
     
     
       7. The method of  claim 1 , wherein the imaging is accomplished using an Mill with a magnetic field strength of 3 tesla. 
     
     
       8. The method of  claim 1 , wherein the images are collected at an image resolution of 512 pixels by 512 pixels and a pixel size of 0.4688 mm. 
     
     
       9. The method of  claim 1 , wherein the first mask filters pixels that are within a contrast range of 0 to 800. 
     
     
       10. The method of  claim 1 , wherein the second mask filters pixels that are within a contrast range of 1250 to 4000. 
     
     
       11. The method of  claim 1 , further comprising transferring the three dimensional image to a three dimensional printer to generate a model. 
     
     
       12. A method of creating a surgical guide, comprising the steps of:
 imaging a patient's joint; 
 collecting a set of images of the patient's joint; 
 generating a first mask on the set of images, wherein the first mask filters pixels that are within a contrast range of 0 to 800; 
 processing the first mask to remove artifacts; 
 generating a second mask on the set of images, wherein the second mask filters pixels that are within a contrast range of 1250 to 4000; 
 processing the second mask to remove artifacts; 
 merging the first and second masks creating a merged mask; 
 generating a third mask by filling in any holes in the merged mask; 
 creating a three dimensional image of the third mask; 
 generating a reverse image of the three dimensional image of the third mask; 
 creating a template from the reverse image; and 
 manufacturing a surgical guide from the template. 
 
     
     
       13. The method of  claim 12 , wherein the surgical guide further includes:
 a body having a first end, a second end, a contacting surface, and a top surface; 
 a tooling guide disposed near the second end and at ad ligament attachment point; 
 the first end adapted to fit in an interstitial space between a set of bones in the joint; and 
 the contacting surface inversely contoured to a shape of the patient's joint anatomy. 
 
     
     
       14. The method of  claim 13 , wherein the tooling guide is selected from a group consisting of a guide cut out, drill guide, and groove tracks. 
     
     
       15. The method of  claim 13 , wherein the tooling guide is adapted to accept a tool selected from a group consisting of an awl, drill, osteotome, dental hatchet, burr, and coring reamer. 
     
     
       16. The method of  claim 12 , further including a step of cropping the merged mask to highlight an attachment point of a ligament. 
     
     
       17. The method of  claim 12 , wherein the images being collected have an image slice thickness of 0.499998 mm and patient image orientation of RAX. 
     
     
       18. The method of  claim 12 , wherein the imaging is accomplished using an MRI with a magnetic field strength of 3 tesla. 
     
     
       19. The method of  claim 12 , wherein the images are collected at an image resolution of 512 pixels by 512 pixels and a pixel size of 0.4688 mm. 
     
     
       20. The method of  claim 12 , further comprising transferring the three dimensional image to a three dimensional printer to generate a model.